Two base balls (masses : m$$_1$$ = 100 g, and m$$_2$$ = 50 g) are thrown. Both of them move with uniform velocity, but the velocity of m$$_2$$ is 1.5 times that of m$$_1$$. The ratio of de Broglie wavelengths $$\lambda$$(m$$_1$$) : $$\lambda$$(m$$_2$$) is given by

The number of unpaired electron in Mn²⁺ ion is

The de-Broglie wavelength ($$\lambda$$) for electron (e), proton (p) and He²⁺ ion ($$\alpha$$) are in the following order. Speed of e, p and $$\alpha$$ are the same

In Bohr model of atom, radius of hydrogen atom in ground state is r₁ and radius of He⁺ ion in ground state is r₂. Which of the following is correct?